Driving the TRXL 1071

[Red Horse]

I have a friend who has a very clean 88 R tandem dump (I think its a 688SX), big rears, and the 1071. He has a guy who drives it from time to time and the guy does not think its a six speed but rather uses the low hole air shift with the stick in other than first. As a matter of fact, he says he takes off with the splitter in "L" and the stick in 2nd. He then says he goes back to 1st "D", then second "D" etc.

Any opinions? This harmful? As the chart for the 1071 says 1st LL is a 23.08 ratio and 1st "D" is a 8.59. When the splitter is in "D" is it a 1 to 1? And constantly driving the respective 5 speeds in the box? I made that assumption and dividing the 1st "D" ratio (8.59) into the LL ratio of 23.08, I come up with a reduction of 2.68.

If that is so, then by starting in 2nd with the splitter in "LL" with a 2nd ratio of 4.59 I come up with a ratio of 13.37 (4.59x2.68). Am I correct?

And again, and more importantly, is he doing this trans harm by running with the splitter in LL in anything but 1st.?

Appreciate any education anyone can give me.

And for the record, the spec sheet for the 1071 shows trhe followqing ratios:

LL 23.08, 1st 8.59, 2nd 4.99, 3rd 2.84, 4th 1.66, 5th 1.00.

Using my "theory" and if you used LL beyond 1st, you would have the following ratios:

LL 23.08 1st D 8.59, 1st LL 23.02, 2nd D 4.99, 2nd LL 13.37, 3rd D 2.84, 3rd LL 7.61, 4th D 1.66, 4th LL 4.44, 5D 1.00

[Lmackattack]

The air shift and 2 stick 6 speeds are 1:1. (direct) in 5th gear. I often start in 1st / low low and shift the main all the way up to 3rd. Then put it in 3rd direct, 4th,5th.

imo..Nothing wrong with using low low in all gears.

I would however suggest that you use caution if you ever try to down shift from direct to low low.. you can split a case if you miss badly..

[Red Horse]

The air shift and 2 stick 6 speeds are 1:1. (direct) in 5th gear. I often start in 1st / low low and shift the main all the way up to 3rd. Then put it in 3rd direct, 4th,5th.

imo..Nothing wrong with using low low in all gears.

I would however suggest that you use caution if you ever try to down shift from direct to low low.. you can split a case if you miss badly..

LM, You are talking about a TRXL 107 right? Note-this is a 1071. There is no way you can get from LL (1st) to 1st direct without the truck coming to a stop. In a 107, LL is 14.10. In a 1071, its 23.08- at least I should say I cant!

[Rob]

LM, You are talking about a TRXL 107 right? Note-this is a 1071. There is no way you can get from LL (1st) to 1st direct without the truck coming to a stop. In a 107, LL is 14.10. In a 1071, its 23.08- at least I should say I cant!

I have the TRXL-1071 in my "Project R-12" truck and can upshift in LL through third, then grab the high range and go back to 1st. The gear split seems fairly close but not as linear as one would like. I've never hauled anything with the truck so cannot vouch for compatibility to use loaded.

Rob

[rick harper]

Use low range only in reverse and 1st hole

[Red Horse]

Use low range only in reverse and 1st hole

Rick,

I'm with you but look at other responses. And the guy I referred to in my original post is not a "rookie" but an experienced owner.

Do ypu agrtee with my "theory" in original post as to how ypou can calculate the ratios IF you are in LL with the stick in 2nd, 3rd, and 4th?

Rob- You are making me feel bad. I used to occasionally drive an R tractor with a TRXL 107 (air shift) pulling 104,000 lbs (MA permits) and that transmission is truly useable as a 6 speed. But the 1071 with a 23.08 ratio in LL and an 8.59 in 1D??? I guess I'm just slow. LL is so low by the time you can complete the shift you -should I say "I" -have lost all momentum- and it won't go-and this is in a 10 wheeler at about 71,000 lbs.

[Rob]

Rick,

I'm with you but look at other responses. And the guy I referred to in my original post is not a "rookie" but an experienced owner.

Do ypu agrtee with my "theory" in original post as to how ypou can calculate the ratios IF you are in LL with the stick in 2nd, 3rd, and 4th?

Rob- You are making me feel bad. I used to occasionally drive an R tractor with a TRXL 107 (air shift) pulling 104,000 lbs (MA permits) and that transmission is truly useable as a 6 speed. But the 1071 with a 23.08 ratio in LL and an 8.59 in 1D??? I guess I'm just slow. LL is so low by the time you can complete the shift you -should I say "I" -have lost all momentum- and it won't go-and this is in a 10 wheeler at about 71,000 lbs.

It's been a couple of years since I've had that truck off the property but I'm certain I upshifted in the low range through three, or four gears while still in low, then switch to high with the compound, and grabbed either first or second with the main. Again the gear spread was close but not linear at all and hard to get the hang. I don't know what the ration is with the compound in low, and the main in third, or fourth.

Rob

[daveigou]

I'm thinking there's more than one version of that six speed, the difference being one has a much lower compound low & reverse. Sounds like that is what he has.

[rick harper]

Here are the verisons of Six speeds. TRXL107 and 1071 or TRXL107A and 1071A. The A denotes air shift ILO of a double stick. The one(1) on the end denotes extra low hole 23.08 ILO 14.10. Why did Mack call it a six speed?? You only use LL in reverse or 1st hole, then use the other five speed when compound is in direct.Thats where you get the six speeds. Drove to many in the last 35 years.

[Lmackattack]

if you have low low in f1st and reverse this may be an early 5 speed? how many reverse gears do you have?

for a common air shift 6 speed The mack manual, and sun visor sticker, said to use Low low in 1st gear only. If your on level ground 1st / low low to 1st /direct is an easy shift. However if we use that practice most people (like you mention) found that you had too slow of road speed (in soft dirt) to get the truck from 1/Low Low into 1/direct before she stopped. thats why I mention that I use Low Low in 1-2-3 to get my speed up,then shift the aux box into Direct,If im in hard dirt I drive it like a 5 speed leaving it in Direct.

If you start in 2nd/low low that is basicly the same as 1st direct because the road speeds are so simmilar. I cant see why anyone would want to go from 2nd/Low Low to 1st direct as your shift will do nothing to increase your speed or change RPMs? So IMHO the best way I have found to shift out of Low Low is to have my road speed up so the truck wont come to a stop before I try for Direct. The manual

thats my .02

[daveigou]

Here are the verisons of Six speeds. TRXL107 and 1071 or TRXL107A and 1071A. The A denotes air shift ILO of a double stick. The one(1) on the end denotes extra low hole 23.08 ILO 14.10. Why did Mack call it a six speed?? You only use LL in reverse or 1st hole, then use the other five speed when compound is in direct.Thats where you get the six speeds. Drove to many in the last 35 years.

Thats what I'm talking about, what shift sequence that may work with the 107 version is not going to work with the 1071.

[RFCDrum]

I always only use the mud stick for 1st and shift it quick with a blip from the jake and go 5 in direct.

[daveigou]

What I did was start off in 2nd / low, instead of giong into 1st, so the shift from 2nd low to second direct was an easy straight line shift, from there on just used the main, I didn't do the math, but I'm not sure that would work with a 1071, because the 2nd/low ratio may actually be lower than 1st direct.

[randyp]

Yall has done give me a headache, and i gots a big head to be hurting like this,,,,randyp

[Red Horse]

What I did was start off in 2nd / low, instead of giong into 1st, so the shift from 2nd low to second direct was an easy straight line shift, from there on just used the main, I didn't do the math, but I'm not sure that would work with a 1071, because the 2nd/low ratio may actually be lower than 1st direct.

If my 2.68 reduction number is correct, then 2nd L (13.37) to 1st D (8.59) would be a 35.7% change. By the same token, 2nd L (13.37) to 2nd D (4.99) would be a 62.7% change-Not good! And again, we are talking 1071 here. Remember in my first post I said I used to pull 104,000 lbs with a 107? The 107 has a reduction of 14.10 in "L". Going from "L" to 1st "D" (8.59) is a 39% change. Very useable and doable. Thst same gear change in a 1071 is a 62.7 % split. Bottom line? Strictly an off road creeper gear.

Bottom line- IF YOU ARE NOT DOING THE TRANS HARM BY RUNNING IN "L" IN ANYTHING BUT 1st- the 2nd L to 1st D gives you the best split. 35.7% Mr Harper says drive it by the book- its a six speed. I agree, but its like a 9 speed Road Ranger. which ever version yoiu have, are there 10 forward speeds? Yes. Is it safe to use the "mystery" gear? I don't know.

[Olivetroad]

Yall has done give me a headache, and i gots a big head to be hurting like this,,,,randyp

'

I am with you - if it does not have a purty set of instructions on a plate on the dash or under the visor, I am blowed up. Too much thinkin'

[Red Horse]

'

I am with you - if it does not have a purty set of instructions on a plate on the dash or under the visor, I am blowed up. Too much thinkin'

That is kinda the point boys. If you followed the dash/visor plate, we wouldn't be having this conversation. As I said when I started this, young friend of mine has this beautiful R that he paid top dollar for. He has a guy driving it from time to time who thinks its a 7 speed-or even a 10 for that matter. I just want to be able to tell him..."don't let him drive it that way" if in fact he is doing damage.

by the way-here is the truck-he let me use it for a few days for some "charity work" at our fairgrounds.

[Rob]

Anybody interested in a manual two stick TRXL-1071? I'm going to be pulling one out of my truck shortly to replace with a T2100 ten speed. Nothing wrong with the trans but I don't need the LL range for anything and wanting the overdrive.

Rob